CONTENTS. xxi 



those of the nearest mainland — On colonization from the 

 nearest source with subsequent modification— Summary of 

 the last and present chapter 405 



CHAPTER XIV. 



MUTUAL AFFINITIES OF ORGANIC BEINGS: MORPHOLOGY — EMBRY- 

 OLOGY — RUDIMBNTABY ORGANS. 



Classification, groups subordinate to groups — Natural system — 

 Rules and difficulties in classification, explained on the 

 theory of descent with modification — Classification of varie- 

 ties—Descent always used in classification — Analogical or 

 adaptive characters — Affinities, general, complex and radiat- 

 ing — Extinction separates and defines groups — Morphology, 

 between members of the same class, between parts of the 

 same individual — Embryology, laws of, explained by varia- 

 tions not supervening at an early age, and being inherited 

 at a corresponding age — Rudimentary organs, their origin 

 explained — Summary 428 



CHAPTER XT. 



RECAPITULATION AND CONCLUSION. 



Recapitulation of the objections to the theory of Natural Selec- 

 tion — Recapitulation of the general and special circum- 

 stances in its favor — Causes of the general belief in the 

 immutability of species — How far the theory of Natural 

 Selection may be extended — EfEects of its adoption on 

 the study of Natural History — Concluding remarks 476 



Glossary op Scientific Terms 507 



Index 531 



